In many situations, a workpiece must be transferred between various stations in an environment in which there are obstacles to the workpiece being transferred. For example, in manufacturing switches, such as those used in burglar alarm systems, the switch includes a spring diaphragm and an armature and it is necessary to attach an electrical contact to each of these switch parts at a precise location so that when installed a proper electrical connection can be made between the switch parts when actuated. However, in order to attach the electrical contact, it must first be transferred to a precise location on the switch part and be maintained at that precise location while it is being attached. The problem which arises, however, is that the spring diaphragm and/or armature typically include ridges and/or depressions surrounding the precise location at which the electrical contact is to be attached. These ridges and depressions form a rough surface and present obstacles to transfer apparatus for simply sliding the electrical contact into position. In addition, once the electrical contact is accurately positioned on the spring diaphragm or armature, it must be maintained in the proper position while a welding operation is performed to weld the elements together.
Accordingly, it is necessary to provide transfer apparatus which will allow workpieces, such as electrical contacts, to be transferred from a supply station to a work station where an operation is to be performed on the workpieces, such as welding, without the ridges and/or depressions of other workpieces at the work station, such as the switch parts, interrupting the transfer of the electrical contacts to their precise location on the switch parts. In addition, there are situations in which the configuration of the work station itself may present obstacles to the transfer of the workpiece to the work station and it is necessary to provide transfer apparatus to avoid such obstacles.
Accordingly, it is an overall objective of the present invention to provide apparatus which is adapted to receive a workpiece and positively transfer it from a supply station to a work station where it is to be worked on without the configuration of the work station or the configuration of other workpieces at the work station interferring with such transfer operation.
In addition, it is also an objective of the present invention to provide apparatus which insures that the transferred workpiece is accurately positioned at a precise location at the work station and is maintained at that precise location while it is being worked on.